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Infra-red monitoring


The Irisys Camera.

Software on the sensor uses count lines (blue and green) to tally vehicle movement.

Same scene as above but from a normal video camera.

The data is gathered by an Irisys system comprising an infra-red camera and analysis software. The system we use also has low quality video for experimental set up and validation purposes. Infra-red generates a total count of cars, cycles and pedestrians for both directions of motion.

February - July 2006

We mounted the system on the roof of the Engineering department, overlooking Fen Causeway.The data was transmitted in real time to the Computer Laboratory via connection to the Granta Backbone network in Engineering. We validated the data by comparison with the video and achieved over 90% accuracy.

October 9th 2006

We mirrored the County Council's annual manual count on Cambridge's radial roads for Huntingdon Road. The Computer Lab's van (donated by Adaptive Broadband) was parked in a layby, close to where the people were counting with clipboards ("Count on Us"). The Irisys system was positioned atop the van's 20 metre mast with a view across both carriageways. We monitored from 7am to 7pm. We validated the data by comparison with the video and achieved over 93% accuracy.

July 17th 2008

The residents of Riverside and nearby roads are concerned about the effect on the volume of traffic in their roads of a proposed development. The former Cambridge Regional College will become dwellings with an underground car park with 158 spaces. The car park will have no exit onto Newmarket Road west of the Elizabeth Way roundabout, but instead, access to the car park will be under the Elizabeth Way Bridge, through the residential streets near Riverside (that are effectively single-lane because of parking) and the congested Newmarket Road east of the roundabout.

We monitored on Beche Road from 8am to 9:30am and under the Elizabeth Way bridge from 3:20pm - 6pm, parking to the west. By July 17th the University term is well over, the private school term has ended and the state school term ends on Friday 18th. We nevertheless monitored substantial use of the road system. In particular, the Riverside cycle track is heavily used.

From September 2008: The project lamp post

We asked the County Council for permission to mount the Irisys camera on a lamp column overlooking Madingley Road, to demonstrate 24/7 monitoring of a radial road. We selected a column with line-of-sight to the Computer Lab's roof and tested wireless communication.

Trial photographs

Irisys trial in October 2006. Alastair puts up the mast. July 2008. The measurement team. July 2008.